This invention relates to the field of electronic interconnections and, more specifically, the provision of the disconnection force and disconnection displacement required for reliable and automatic disconnection for small electronic modules or the like as well as at least partial ejection thereof whenever the modules are difficult to grasp while being unlatched and removed from a host receiving device.
Increasingly, computers are being connected to other computers and servers using fiber-optic cable or coaxial cable. Efficient connecting or networking of the computers and servers requires the interchangeability of transceiver modules utilized to connect the coaxial or fiber-optic cable to the electronics of a computer or server. Interchangeability of transceiver modules is necessary both to accommodate those existing differences between the electrical signals carried over coaxial cable and the light pulse signals carried on a fiber-optic cable, and then to convert the signals between the electronic signals used by a computer and the optical signals carried on a fiber optic cable network.
U.S. Pat. No. 5,980,324, GUIDE RAIL SYSTEM WITH INTEGRATED WEDGE CONNECTOR FOR REMOVABLE TRANSCEIVER, issued Nov. 9,1999, to Jerry Berg et al., discloses one version of a kick-out spring in a transceiver port of a computer or server.
Currently being established is a standard for the interconnection interface and the transceiver modules to enable the various component suppliers of the devices to supply modules to be completely interchangeable without regard to manufacturing sources.
The transceiver modules typically are densely populated on an exterior panel of a computer housing or server housing and, accordingly, are difficult to grasp and extract from their respective ports, primarily due to size and spacing between adjacent ports. The difficulty of grasping the transceiver modules is exacerbated both by a very small surface of a fully inserted and latched transceiver module which protrudes from the computer or server housing, and the close proximity of similar adjacent modules does not allow adequate finger space to reach in order to grasp the modules.
It thus becomes necessary to eject the transceiver module, at least partially, from the computer housing or server housing once a transceiver module is unlatched. Typically, this is accomplished by one or more kick-out springs residing within the computer or server housing and generally within the electromagnetic interference shield that partially encloses the connector to which the transceiver module is engaged and connected. The kick-out springs are engageable by the transceiver module and compressed, deflected or deformed as the transceiver module is forced into a mating connection with the connector and latched for retention within the computer or server housing.
A transceiver module latch retains the transceiver module connected and installed with the computer or server electronics. Whenever this latch is released, the kick-out springs are intended to release their stored energy and restore to their undeformed state. This action pushes the transceiver module away from the mating connection to initiate disconnection from the connector in the computer or server.
This displacement of the transceiver module caused by the kick-out spring also moves the transceiver module and its latch mechanism, carried on the transceiver module, outward to the point that the latch cannot relatch, thus further retaining the transceiver module in a connected condition.
While the transceiver module protrudes a small distance from the computer or server housing in its fully latched and installed position, the small amount of the transceiver module protruding from the housing is difficult, if not insufficient, to be easily grasped by fingers in order to extract the transceiver module from the housing.
The amount of transceiver module extending from the housing is essentially the only visual indicator of connection or disconnection of the transceiver module with respect to the mating connector resident within the computer or server housing. If the module is not reliably seated and connected to the host connector, it may not be readily apparent based only on visual inspection.
Whenever the frictional forces of engagement and connection of the connector on the transceiver module with the connector resident within the host computer or server housing are excessive relative to the kick-out spring force, the transceiver module may not adequately respond to the unlatching of the transceiver module; and once the unlatching force is released, the latch may not have displaced sufficiently to prevent the latch from re-engaging the mating latch surface. Once this occurs, the transceiver module neither disconnects nor partially ejects from the computer or server housing as originally intended.
Under these circumstances, removal of a transceiver module requires connecting a dummy cable connector or similar device and pulling thereon while the latch is released again. This may overstress the cable or cable fitting and damage it to the point of being unusable. Alternatively, a tool must be secured and engaged with some portion of the transceiver module, and then the transceiver module must be forcibly pulled to disconnect the connectors and remove the transceiver module while simultaneously the module is latched. This procedure poses a substantial risk of damaging the transceiver module, a relatively expensive item.
The causes for improper and insufficient ejection of the transceiver modules may be due not only to excessive frictional forces between the connectors, but also due to insufficient deformation of the kick-out spring during insertion. Such insufficient deformation can result from a permanent set in the kick-out spring resulting in inadequate restoration movement and lack of adequate kick-out spring force over the entire range of movement required to fully disengage the mating connectors and to eject at least partially the transceiver module.
It is an object of the invention to insure reliable disconnection of a module from a host computer or server.
It is another object of the invention to insure the adequate displacement of the module to prevent relatching of the module in its connected, installed condition once unlatched for removal.
It is an additional object of the invention to provide a disconnecting and displacing force over an extended range of movement of the module.
It is a further object of the invention to insure displacement of the module sufficient to provide a ready manual grasp of the module for easy removal, upon unlatching and release.
The foregoing objects are not intended to limit the scope of the invention in any manner and should not be interpreted as doing so.
Other objects of the invention will become apparent to one of skill in the art of electrical connections and devices for accomplishing disconnection of electrical connectors with a full and complete understanding of the invention.
In order to overcome the frictional forces between the connectors of a computer/server and the transceiver module and then to eject the transceiver module from its port in the computer or server port, an ejection or kick-out spring is incorporated into a computer which engages and resists the insertion of the transceiver module. By deforming during insertion of the transceiver module, the kick-out spring stores energy which then is available to eject and disconnect the transceiver module upon release.
At least one version of this kick-out spring as discussed herein utilizes a pair of cantilevered beam springs supported by an electromagnetic interference shield, which at least partially encloses the connector of the host computer and into which the transceiver module is inserted. Due to size limitations, the kick-out spring is relatively weak and has a limited range of deformation before becoming over-stressed.
The range of motion through which a kick-out spring may be displaced or deformed is inherently limited by the design and choice of materials for the spring. The addition of an engaging secondary kick-out spring to the transceiver module structure enhances the disconnection and ejection. The secondary kick-out springs engage the primary kick-out springs and deflect in response to insertion of the transceiver module into the port. The combination of kick-out springs extends the effective range over which the disengagement or kick-out force is applied to the transceiver module. Moreover, the secondary springs can increase the initial kick-out force at the point of latch release. Latching mechanisms may be of varied types and may incorporate any such mechanism disclosed in any of the various cross-referenced related U.S. patent applications above.
The pair of cantilevered beam springs engage each other, and both deflect in direct relation to their respective spring force constants. These springs may be designed to provide the minimum disconnection force at a deformation equaling to and corresponding to force exerted at initial contact between the connectors of the computer or server and the transceiver module with no forced frictional engagement between the connector contacts or connector housings.
If the spring force constants of the opposing kick-out and secondary springs are substantially equal, both opposing springs will deform or deflect a substantially similar amount. If one of the opposing springs has a spring force constant greater than the other, the spring with the smaller spring force constant will deflect a greater amount than the spring with the larger spring force constant. The spring with the larger spring force constant may cause the other opposing spring to deform or deflect beyond its yield point and acquire a permanent set or deformation, thereby reducing its effectiveness and its ability to exert its design force on the opposing spring or, subsequently, it may cause the overly deflected spring to break.
To overcome this possible physical failure and prevent a reduction in effectiveness, the spring with the smaller spring force constant may be blocked at its maximum design limit of travel by an over-travel stop. The weaker spring will abut the over-travel stop when fully deflected by the stronger spring and the stronger spring then may continue to deflect as it is further loaded. This will permit the opposing springs to exert disconnection and ejection forces over a larger span of linear travel of the transceiver module and will insure that adequate ejection forces remain available from the kick-out springs to be exerted on the transceiver module once the transceiver module connector has been unlatched and disconnected from the mating connector.
The span of linear travel thus will be extended to be the sum of the deflections of the two opposing springs. Typically the weaker spring both will be formed integrally with the transceiver module and be molded of plastic. The stronger spring typically will be a metal spring and thus incorporated into the computer or servers. Additionally, it may be a part of or attached to a metal electromagnetic interference shield which at least partially encloses the computer connector of the port. The over-travel stops may be advantageously molded into the frame or chassis of the transceiver module.
Metal springs may be attached in conventional manner to the transceiver module chassis or frame if the use of integrally molded plastic springs is not desired. If metal, the transceiver module springs may be cantilevered leaf springs, collapsible leaf springs or coil springs as long as the other criteria set forth for the transceiver module springs are met.
This Summary of the Invention is intended to be only a summary and not be used to limit the invention in any manner.